Lab CPT codes describe the laboratory tests a provider or lab bills for, from a basic metabolic panel to a urine culture. Most fall in the 80000 to 89999 range of the CPT code set.
The most commonly billed lab CPT codes are 80048 (basic metabolic panel), 80053 (comprehensive metabolic panel), 85025 (complete blood count with automated differential), 80061 (lipid panel), 83036 (hemoglobin A1c), 84443 (TSH) and 81001 (urinalysis with microscopy). The blood draw itself is billed separately with 36415. Getting paid also depends on panel rules, the right modifiers, a valid CLIA certificate, and a diagnosis code that shows why each test was needed. For example, an elevated white blood cell count is coded as described in our leukocytosis ICD-10 guide. When a BMP shows low potassium and the provider documents it, see our hypokalemia ICD-10 guide for coding E87.6.
Do not bill a panel code unless every test in the panel was performed. If one component was not run, bill the tests that were performed individually. If extra tests were run, bill them separately in addition to the panel.
This guide lists the most common lab CPT codes by category, explains panel rules and lab modifiers, and covers the medical necessity and CLIA requirements behind most lab denials.
Key Takeaways
- Lab CPT codes run from 80047 to 89398, covering panels, chemistry, hematology, urinalysis, microbiology and more.
- Panel codes such as 80048 and 80053 require every listed test. Do not report two panels that share the same tests from one collection.
- Venipuncture (36415) is billed separately from the tests.
- Medicare needs a valid CLIA certificate number on lab claims, and modifier QW for CLIA-waived tests.
- Modifier 90 marks a test sent to a reference lab. Modifier 91 marks a repeat test done for clinical reasons on the same day.
- Each test needs a diagnosis code that supports medical necessity, and some tests have frequency limits.
What Are Lab CPT Codes?
CPT codes are maintained by the American Medical Association. The Pathology and Laboratory section, codes 80047 to 89398, covers tests done on specimens such as blood, urine, tissue and swabs. Each code describes what was tested and, for many tests, how it was tested.
Lab CPT codes tell the payer which test was performed. ICD-10-CM diagnosis codes tell the payer why. Both are needed for the claim to be paid. For a primer on how the code sets fit together, see understanding CPT, ICD-10 and HCPCS codes.
Most Common Lab CPT Codes
| CPT code | Test | Category |
|---|---|---|
| 80048 | Basic metabolic panel (BMP) | Organ or disease panel |
| 80053 | Comprehensive metabolic panel (CMP) | Organ or disease panel |
| 80061 | Lipid panel | Organ or disease panel |
| 85025 | Complete blood count (CBC) with automated differential | Hematology |
| 85027 | Complete blood count (CBC), automated, without differential | Hematology |
| 83036 | Hemoglobin A1c | Chemistry |
| 84443 | Thyroid stimulating hormone (TSH) | Chemistry |
| 84439 | Free thyroxine (free T4) | Chemistry |
| 82947 | Glucose, quantitative, blood | Chemistry |
| 82306 | Vitamin D, 25-hydroxy | Chemistry |
| 84153 | Prostate specific antigen (PSA), total | Chemistry |
| 85610 | Prothrombin time (PT) | Coagulation |
| 81001 | Urinalysis, automated, with microscopy | Urinalysis |
| 87086 | Urine culture, quantitative colony count | Microbiology |
| 87880 | Rapid strep A test (immunoassay with direct optical observation) | Microbiology |
| 36415 | Collection of venous blood by venipuncture | Specimen collection |
Panel Codes and What They Include
Organ and disease panels bundle common tests into one code. The panel is billed only when every listed test is performed.
| CPT code | Panel | Tests included |
|---|---|---|
| 80048 | Basic metabolic panel | Calcium (total), carbon dioxide, chloride, creatinine, glucose, potassium, sodium, urea nitrogen (BUN) |
| 80053 | Comprehensive metabolic panel | The BMP tests plus albumin, alkaline phosphatase, ALT, AST, total bilirubin and total protein |
| 80061 | Lipid panel | Total cholesterol, HDL cholesterol, triglycerides |
| 80076 | Hepatic function panel | Albumin, total bilirubin, direct bilirubin, alkaline phosphatase, total protein, ALT, AST |
| 80051 | Electrolyte panel | Carbon dioxide, chloride, potassium, sodium |
Overlapping panels from one draw. CPT instructs not to report two or more panels that include any of the same tests from the same collection. For example, a CMP (80053) and a hepatic function panel (80076) share several tests. Report the CMP, then bill only the extra test, such as direct bilirubin, on its own.
Urinalysis CPT Codes
Urinalysis codes depend on whether the test is automated and whether microscopy is done.
| CPT code | Method | Microscopy |
|---|---|---|
| 81000 | Non-automated (dipstick or tablet) | With microscopy |
| 81001 | Automated | With microscopy |
| 81002 | Non-automated (dipstick or tablet) | Without microscopy |
| 81003 | Automated | Without microscopy |
Lab Modifiers You Need to Know
| Modifier | Meaning | When to use it |
|---|---|---|
| QW | CLIA-waived test | Medicare and many other payers require it on waived tests done in the office |
| 90 | Reference (outside) laboratory | The billing provider sent the test to an outside lab, where payer rules allow this |
| 91 | Repeat clinical diagnostic laboratory test | The same test repeated on the same day to get a new result for clinical care |
| 59 or XU | Distinct procedural service | Only when documentation supports a separate service and an NCCI edit applies |
Modifier 91 is not for re-running a test. Do not use it when a test is repeated because of a specimen or equipment problem, or to confirm the first result. Use it only when the provider needs a new result to manage the patient.
How to Bill Lab Services: Step by Step
- Check the order. Confirm a signed order or documented intent to order for each test, from a provider authorized to order it.
- Pick the right code. Match the code to the test and method actually performed, and apply panel rules.
- Add the modifiers. Use QW, 90 or 91 where they apply.
- Link the diagnosis. Point each test to the ICD-10-CM code that supports why it was ordered.
- Include the CLIA number. Medicare lab claims need a valid CLIA certificate number that covers the tests billed.
- Bill the draw. Add 36415 when blood was drawn by venipuncture.
- Check coverage and frequency. Review national and local coverage rules, and give the patient an ABN when Medicare may not cover the test.
Medical Necessity and Frequency Limits
Lab tests are among the most common services denied for medical necessity. Medicare publishes national coverage determinations (NCDs) for many lab tests, listing the diagnoses that support coverage and how often a test is covered. For example, Medicare’s NCD for glycated hemoglobin generally covers testing for diabetes management no more than once every three months, unless the record supports more frequent testing.
- Link every test to a diagnosis that supports it
- Check NCD and LCD covered diagnosis lists before billing
- Track the last covered date for tests with frequency limits
- Give an Advance Beneficiary Notice (ABN) before testing when Medicare may deny it
- Do not bill screening tests with diagnostic codes unless the provider documents a reason
Diagnosis mismatches on lab claims often show up as CO-11 denials. For a wider look at lab billing problems, see lab billing challenges and solutions.
Common Lab Coding Errors
Billing a panel with a missing test. Bill the tests performed individually instead.
Unbundling a panel. When all panel tests are performed, billing them one by one instead of the panel code is unbundling.
Missing QW on waived tests. Medicare denies waived tests from an office lab without it.
Wrong CBC code. 85025 includes the automated differential. 85027 does not. Bill the one that matches the test run.
Missing or wrong CLIA number. The CLIA certificate must be valid and must cover the complexity of the test billed.
How Steady Medical Billing Helps
Lab claims are high in volume and low in dollar value, so small error rates add up quickly. Steady Medical Billing’s medical coding services check panel rules, modifiers, CLIA details and diagnosis links before claims go out. For labs, our laboratory billing services and laboratory credentialing services cover the full revenue cycle. Learn more about the benefits of outsourcing lab billing.
Seeing lab denials for medical necessity, panels or modifiers? Request a free medical billing and coding audit from Steady Medical Billing.
Frequently Asked Questions
What are the most common lab CPT codes?
The most common include 80048 (BMP), 80053 (CMP), 85025 (CBC with differential), 80061 (lipid panel), 83036 (hemoglobin A1c), 84443 (TSH), 81001 (urinalysis with microscopy) and 36415 (venipuncture).
What is the CPT code for a CBC?
Use 85025 for a CBC with automated differential and 85027 for a CBC without a differential.
What is the difference between 80048 and 80053?
80048 is the basic metabolic panel, with 8 tests. 80053 is the comprehensive metabolic panel, which adds albumin, alkaline phosphatase, ALT, AST, total bilirubin and total protein. Do not bill both from the same blood draw.
Is the blood draw billed separately from the lab test?
Yes. Venipuncture is billed with CPT 36415, in addition to the codes for the tests performed.
What does modifier QW mean on a lab claim?
QW shows that the test is CLIA-waived. Medicare and many other payers require it on waived tests, such as many rapid tests done in the office.
When should modifier 91 be used?
Use modifier 91 when the same lab test is repeated on the same day to get a new result for patient care. Do not use it when a test is rerun because of a problem with the specimen or equipment.
